in. to start harassing someone about a personal problem; to annoy someone.
I'll get on Tom's case about being late so much.I'm sorry, I won't get on your case anymore.
Idiom
get on someone's caseget on (someone's) case
informal to criticize someone in an annoying way for something that they have done.
I just don't want him getting on my case for being late for work.
(redirected from get on someone's case)
get on (one's) case
To start bothering someone about something. Oh, don't worry—I'll get on Pat's case until he agrees to go to the interview. It's too good an opportunity to pass up.
get on someone’s case
in. to start harassing someone about a personal problem; to annoy someone. (Compare this with get off someone’s case.) I’ll get on Tom’s case about being late so much.